Just spotted this one:
A Jurassic avialan dinosaur from China resolves the early phylogenetic
history of birds
Pascal Godefroit, Andrea Cau, Hu Dong-Yu, François Escuillié,
Wu Wenhao & Gareth Dyke
AffiliationsContributionsCorresponding author
Nature 498, 359­362 (20 June 2013) doi:10.1038/nature12168
The recent discovery of small paravian theropod dinosaurs with
well-preserved feathers in the Middle­Late Jurassic Tiaojishan Formation of
Liaoning Province (northeastern China)1, 2, 3, 4 has challenged the pivotal
position of Archaeopteryx3, 4, regarded from its discovery to be the most
basal bird. Removing Archaeopteryx from the base of Avialae to nest within
Deinonychosauria implies that typical bird flight, powered by the forelimbs
only, either evolved at least twice, or was subsequently lost or modified in
some deinonychosaurians3, 5. Here we describe the complete skeleton of a new
paravian from the Tiaojishan Formation of Liaoning Province, China.
Including this new taxon in a comprehensive phylogenetic analysis for basal
Paraves does the following: (1) it recovers it as the basal-most avialan;
(2) it confirms the avialan status of Archaeopteryx; (3) it places
Troodontidae as the sister-group to Avialae; (4) it supports a single origin
of powered flight within Paraves; and (5) it implies that the early
diversification of Paraves and Avialae took place in the Middle­Late
Jurassic period.